Casing protector



Sept. 9, 1958 w. B. BUCK CASING PROTECTOR Filed oct. 2, 195s 2 Sheets-Shea?. 1

F/G' 8 INVENTOR.

w B BUCK WHL/MAM* ATTORNEYS CASFNG'PRDTECTOR twilliam FB. Buck, lrlahoma `City, -'Okla., assignor to Phillips Petroleum Company, za fcorporation of Dela- --ware 'Application ctober 2, 1953,SerialNo. 383,727

6 Claims. (Cl. 166-218) zThisinvention relatesto -a methodofand apparatus rfor repalring.V and protecting well-casings.

In vthe drilling, servicing Aand pumping -of oil :Wells V'various instruments and tools are lowered'intoithe-.well `fon cables,-tubing or rods. yBecause these wells ,seldom if .:everrare entirely vertical andbecause .ofthe depths to -which they are drilled, it is found that the.y casing often :becomes unduly worn in certain regions by abrasion of Vvtheicables, tubing or rods against the casing-wall. :For example, inaproducing well yit often-becomes;,necessary -to lowercablevdrilling tools, bailers, cleaning tools and -the vlike finto `the well. `:the cable suspending these tools-and the casing wall can lbedetected'by a casing caliper survey 'to determine the tdepths attwhich abrasion occurs. -When such abrasion is -.detected it becomesl important to repair orvprotect the `casing-to prevent holes from being wornftherethrough.

Any excessive friction between `It issof course desirable that such a repair operation be carried out without removing the casingtrom the-well. `VIneaccordance with thepresent invention, a-system for making such repairs is provided.

.This-.invention `comprises generally-an improved methy:od-tof and apparatusfor repairing and protecting -well 'casings by inserting elastic vsleeve members therein -at s: selected xdepths. .-:into: the casing so as to remain inplace by the'. elastic :properties of the members. -ffsleeve members in eiect become a part of thecasingl 4:andremain in place during subsequent production vand :servicing operations. The apparatus for inserting vthese ;sleeve members comprises generally a1hollow cylinder which is of slightly smaller outside diameter ythan the #inner diameter of the casing. The protective vsleeve memrzberis compressed and positioned Within this cylinder. 1A :Jpiston is provided in conjunctionwiththe cylinder; such yahat the sleeve member can be discharged fromy thev cyl- ;frinder at a selected depth inthe well. Inoneembodiment .-.oflithe apparatus, the piston and sleeve -member areheld z-vstationary and the cylinder is moved rwith respect4 thereto. `1 'In a second embodiment, the cylinder remainsstationary .and'f-both the piston and sleeve member are'moved there- 'thr0ugh. This relative movement between thev pistonand These sleeve members yare -ttedr' snugly When so positioned the cylinder can be effected byv a compressed airl systemwhich :is actuated from the surface of the earth.

Accordingly, it is an'object of thisinventionto. provide an improved method of and apparatus'for protectingwell casings by inserting elasticsleeve members therein at t iselected depths.

Another object is to providek a method of repairingand -fiprotecting well casings without removing `the casing J from the well.

vA`further object is to provide apparatusffor-inserting elastic sleeve members inside aswell casing.

IA'further object is to provide protectivewsleeve mem- ".bers for use in cased wells.

yVarious other objects, advantages and features of ythis invention should become apparent from Athe-following v Patented Sept. 9, 1958 i ce l 2 ldetailed description `taken in conjunctionwiththe accom- ;panying 4drawing yin which:

.-"Figurelis a vertical sectionaliview ofa Awell illustrat- -fing facprotective .sleevezpositioned therein and `a portion 'of the sleeve positioning apparatus ofithis invention;

Figure .'2 illustrates vone embodiment ofthe Iprotective l,sleeve imember;

Figure 3 is .a view, .shown :partially `in section, of a rst .embodiment of the -'down'hole sleeve insertingmechanism;

:Figureg4fis a sectional view-taken along line 4-14 -in ,Figure 3;

Figure 5 is a view, shown partially inssection,` of .a second .embodiment of -the down-hole .sleeve inserting mechanism;

:inwparticularthere is illustrated asection of a AWell .10

:having .a--casing 11 positioned ftherein. The upper portionofthe-sleeve :inserting:mechanismilZ of this inven- 1 tion'v is :shown suspended,` in, well r1@ Aby a. cable @13 which passes over :,agpulleyf14xat;thefsurface of `the earth-and which'isfattache'd :at itsupperend. toa lreel :15 that is `driven by a; suitable source-of;power,;not'shown. IAn 4odometer.. 16 rests against .cable 13 to. 'providev an rindica- 'ptionsof lthe depth"to==whichrmember` 12 is'suspendedin rwell 10. :Cable13.:enclosesnfan;,electrical lead lwhichter- ^minates at its upper vrendin av` slipl ring 17. attached lto 'reel 15. A `brush 18-is in engagement'with ,slip ring :'17. .Br.ush=18, .in-turn,v isl connected by'fa lead .19.and a switch 20m-one terminal of a voltagensourceZl, thelsecond terminal ,of which isY grounded.

The lower sectionl of .welllsj isrshown as'being curved :inzsomewhat of-anexaggerated manner to illustrate that #wells.oftenffdeviatesfrom. a vertical'lline. l-fThus, ,Whenever tools: are lowered into ,the well-thezsuspendingf cable .tends to-rub against casing 11at regions such as :indicated /by 23. -InaccordancewvithV the present invention elastic Fsleeve members 24 are positioned `in Iztl1ewell wherevervr there isza tendency forfthe cable'to rub :excessively: against the casing wall.

,InFigure 2 Vtherenis `illustrated a-'rst embodiment -rof L cylindrical sleeve member *24 Awhich .preferably is; made not rubber ,or somerubberflike polymerized -synthetic Amaterial, such as4 synthetic Vrubber for neoprene, :which is vresistantxto oil. ,S1eeve.124.is suiciently'rigid Yto resist :the abrasive action of cables rubbing thereagainst-and isv suiciently elastic ito' engagecasing- 11 Vin a tight ',iit.

For reasons that Will'become apparenthereinafter,` sleeve "-24 can'be yprovidedwithfa 'rib-25..which` is constructed offhighly "elastic material.

The sleeve positioning.,apparatusl'lZ. shown in' Figure 1 is illustrated indetailinwFigure 3. 'This-apparatuscom- Aprises` generally a housing'Z'l. which is attached fatlits upperend 4to cable13. The upper portion of 4housing 27 contains.` a tank' 28fwhich is vfilled with a compressed uid such as air. Afchamberl 30 is formed inl housing '27 beneath tank "28 and apiston 31 is positioned'for movementl therein. A second chamber 32 is formed Abe- 'neath piston nv31. A conduit 33 communicates beneath chamber-32 and tank 28; and a valve 34, which is oper ated by a solenoid 35, is disposed in conduit 33. One .terminal of solenoid'35 is connected to a lead 37 which `upper `end in, slip. ring 17 vThesecond terminaloisolenoid 37 is grounded on housing 27. A connecting rod 38 is fastened at its upper end to piston 31 and at its lower end to a hub 40. A ring 41 is connected to hub 40 by a plurality of spokes 42. An elongated hollow cylindrical member 43 is threaded at its upper end to ring 41 and extends downwardly therefrom in close proximity to well casing 11. Sleeve member 24 is tted inside cylinder 43 by suitable compression of sleeve 24, this operation being performed before assembly 12 is lowered into well 10. A piston 45 is positioned within cylinder 43 above sleeve 24 and is rigidly connected to housing 27 by a plurality of rods 46 that are connected at their upper ends to a ring 47 which is threaded to housing 27. Piston 45 is provided with a depending annular portion 49, the outer diameter of which is slightly less than the inner diameter of sleeve 24.

When it is desired to position sleeve 24 in casing 11, assembly 12 is lowered into the well until sleeve 24 is adjacent the region to be protected. At this point switch is closed which energizes solenoid 35 to open valve 34. The pressure applied from tank 28 to chamber 32 moves piston 31 upwardly, and this in turn moves cylinder 43 upwardly a like amount. Sleeve 24, however, remains stationary because piston 4S, which is in engagement therewith, is rigidly connected to housing 27. As soon as cylinder 43 is removed from sleeve 24 the sleeve expands outwardly to engage casing 11. It is desired that valve 34 have a sufficiently small opening that piston 31 moves at a relatively slow rate. In this manner the lower portion of sleeve 24 first engages casing 11. Since sleeve 24 must be formed of a fairly rigid material it is sometimes desirable to place a rib of a highly elastic material near the bottom thereof such that this rib engages casing 11 immediately and retains sleeve 21 in position until the main body of material has expanded suficiently to engage casing 11 in a tight fit. Depending portion 49 of piston tends to retain sleeve 24 in proper alignment and resists any tendency of the top end of the sleeve to buckle when cylinder 43 is moved initially. If necessary, a suitable lubricant can be applied to sleeve 24 to facilitate release of the sleeve from cylinder 43.

In Figure 5 there is illustrated a second embodiment of the sleeve positioning mechanism of this invention. The apparatus of Figure 5 comprises a cylinder 53 which is attached at its upper end to a housing 27. Cylinder 53 is approximately twice as long as sleeve 24, which is fitted in the lower portion thereof. A plunger 54 having an annular depending portion 55 is attached at its upper end to a connecting rod 56. Rod 56 is in turn attached at its upper end to a piston 58 which is free to move through a chamber 57 in housing 27. A chamber 59 above piston 58 is in communication with tank 28 through a conduit 33'. Closure of switch 20 results in pressure being applied to chamber 59 to force plunger 54 downwardly with respect to cylinder 53. This in turn operates to expel sleeve 24 from cylinder 53. A stop ring 60 is provided at the bottom of chamber 53 to prevent plunger 54 and piston 58 from falling out of cylinder 53.

The apparatus illustrated in Figure 3 is generally preferred to the apparatus of Figure 5 because in the former the only force tending to retain sleeve 24 in cylinder 43 is the frictional force between these two members. In the apparatus of Figure 5 there is the additional frictional force of sleeve 24 being pushed along casing 11 after the lower end of sleeve 24 has been expelled from cylinder 53. However, for some applications the apparatus of Figure 5 can be used to advantage. While a compressed air piston moving system has been illustrated, it should be apparent that other mechanism can be employed if desired. For example, a hydraulic or an electrical system can be used to move cylinder 43 or plunger 54.

For some operations it is necessary that the sleeve member be formed of an extremely rigid material in order to afford the desired protection of the casing wall. Accordingly, it is sometimes necessary to bend the sleeve Cil member in somewhat the manner illustrated in Figure 7 in order that such a sleeve 24 can be inserted into cylinder 43. When it is necessary to bend sleeve 24' in this manner it is generally desirable to employ a piston 45 which is substantially fiat on the bottom surface. This particular configuration is illustrated in Figure 8. If such a sleeve 24 is employed in conjunction with the apparatus of Figure 5, plunger 54 preferably is formed with a flat lower surface similar to piston 45. Otherwise the operation of positioning the sleeve in the casing is the same as previously described.

While this invention has been described in conjunction with present preferred embodiments thereof it should be apparent that the invention is not limited thereto.

What is claimed is:

l. Apparatus for placing a previously compressed, generally cylindrical hollow elastic member in a well, comprising a housing defining a piston chamber, a first piston slidably disposed in said chamber, a hollow cylinder having an outer diameter slightly less than the diameter of said well and an unobstructed open end, said cylinder adapted to hold said elastic member under compression, a second piston slidably disposed in said cylinder, said cylinder being connected to one of said first piston and housing members and said second piston connected to the other of said members, and means operable to move said first piston whereby said second piston moves relative to said cylinder to release said elastic member through said open end of said cylinder so as to effect placing of said elastic member in said well by allowing said elastic member to expand into engagement with the wall of said well.

2. The combination in accordance with claim l wherein a first segment of said second piston is of outer diameter substantially the same as the inner diameter of said cylinder and wherein a second segment of said second piston is of outer diameter less than the inner diameter of the elastic member, the elastic member enclosing said second segment of said second piston when positioned within said cylinder.

3. Apparatus for placing a previously compressed, generally cylindrical hollow elastic member in a tubular object within a well, comprising a housing defining a piston chamber, said housing adapted to be lowered in said well, a rst piston slidably disposed in said piston chamber, a source of fluid pressure in said housing, valved conduit means connecting said source of fiuid pressure with said chamber, the valve in said valved conduit being electrically operated, a hollow cylinder having an unobstructed open end and adapted to hold said elastic member under compression, said cylinder having an outer diameter slightly less than the inner diameter of said tubular object, a second piston slidably disposed in said cylinder, said cylinder being connected to one of said first piston and housing members and said second piston connected to the other of said members, and means positioned at the surface of said well to actuate said valve whereby said fluid pressure acts on said first piston to cause its movement, whereby said second piston moves relative to said cylinder to release said elastic member through said open end of said cylinder so as to effect placing of said elastic member in said tubular object by allowing said elastic member to expand into engagement with said tubular object.

4. Apparatus according to claim 3 wherein said valve is a solenoid-actuated valve.

5. Apparatus for installing a previously compressed, generally cylindrical hollow elastic member in the casing of a well, comprising a housing defining a piston chamber, said housing adapted to be lowered in said well near the point of installation, a first piston slidably disposed in said chamber, a source of fluid pressure in said housing, valved conduit means connecting a source of fluid pressure with said chamber beneath said tirst piston, the valve in said valved conduit being electrically operated, a hollow cylinder having an unobstructed open end and y asuma adapted to hold said elastic member under compression, said cylinder having an outer diameter slightly less than the inner diameter of said casing, means connecting said rst piston with said cylinder, a second piston slidably disposed in said cylinder, said second piston connected to said housing, and means positioned at the surface of said Well to actuate said valve whereby said uid pressure acts on said first piston to cause its movement and said cylinder to move relative to said second piston so as to release said elastic member through said open end of said cylinder to elect installation of said elastic member in said casing by allowing said elastic member to expand into engagement with said casing.

6. Apparatus for installing a previously compressed, generally cylindrical hollow elastic member in the casing of a Well, comprising a housing defining a piston charnber, said housing adapted to be lowered in said well near the point of installation, a rst piston slidably disposed in said chamber, a source of iluid pressure in said housing, valved conduit means connecting a source of uid pressure with said chamber above said rst piston, the valve in said valved conduit being electrically operated, a hollow cylinder having an unobstructed open end and adapted to hold said elastic member under compression, said cylinder having an outer diameter slightly less than the inner diameter of said casing', means connecting said cylinder with said housing, a second piston slidably disposed in said cylinder, said iirst and second pistons being connected together, and means positioned at the surface of said well to actuate said valve whereby said fluid pressure acts on said iirst piston Vto cause its movement and said second piston to move relative to said cylinder so as to release said elastic member through said open end of said cylinder to effect installation of said member in said casing by allowing said elastic member to expand into engagement with said casing.

References Cited in the tile of this patent UNITED STATES PATENTS 790,208 Hubbard May 16, 1905 1,262,107 Sheasley Apr. 9, 1918 2,107,784 Gardner Feb. 8, 1938 2,196,652 Baker Apr. 9, 1940 2,642,268 Armentrout June 16, 1953 2,693,633 Wood Nov. 9, 1954 2,721,058 Boice Oct. 18, 1955 FOREIGN PATENTS 27,764 Austria Mar. 11, 1907 

